When we describe the energy of a particle as quantized, we mean that only certain values of energy are allowed. ... It can only gain the exact amount of energy needed to reach one of the higher energy levels, and it can only lose the exact amount of energy needed to reach a lower energy level.

What is quantized energy level?

Energy is quantized in some systems, meaning that the system can have only certain energies and not a continuum of energies, unlike the classical case. This would be like having only certain speeds at which a car can travel because its kinetic energy can have only certain values.

Why are energy levels said to be quantized?

Electrons are said to be quantized because they need a quantum of energy to move to a different sublevel. ... When atoms absorb energy, electrons move into higher energy levels. These electrons lose energy by emitting light when they return to lower energy levels.